Automatic slack adjuster



" Jan. 19, 1932. H. E. ANDERSON AUTOMATIC SLACK ADJUSTER M Filed Sept. 12, 1930 2 Sheets-Sheet l INVENTOR.

ATTORNEY.

Jan. 19, 1932. H. E. ANDERSON AUTOMATIC SLACK ADJUSTER Filed Sept. 12. 1950 2 Sheets-Sheet 2 INVENTOR.

EE I v r a 13 M A TTORNEY.

Patented Jan. 19, 1932 UNITED STA-res: Parent oFFrc HARLEY E. ANDERSON, OF KANSASGITY, MISSOURI, ASSIGNOR T GUSTINQBACON l MANUFACTURING G 01E. KANSAS CITY,"MISSOURI,..A.CORPORATION OF. MISSOURI AUTOMATIC SLACK ADJUSTER Application'filed' September 12, 1930; SeriallNo. 481,418.

My invention relates to an automatic slack: adjusting. device, and it has for its object to. provide animproved structure constituting a connection between the usual horizontal iicylinder lever and the live truck lever of a railroad car, of such a nature as to compensate for different thicknesses of brake shoes, and to maintain the proper length of said lever, under all conditions of use.

Further objects and advantages of the invention will be set forth in the detailed description which follows.

In the accompanying drawings:

Fig. 1 is a plan view,

Fig. 2is a side elevation,

Fig. 8 a vertical sectional View of my improved take-up or slack adjuster,

Fig. 4 is a View, partly in side elevation and partly in section, of a modified formof the invention, and

Fig. 5 1s a transverse vertlcal sectional vlew upon line 5-5, of Fig. 2.

Similar reference numerals refer to similar parts throughout the entire description.

The drawings show the usual horizontally movable cylinder lever 5 of a railroad-car air brake, and the live truck lever 6, the movement of which applies or releases the brake shoe (not shown In the form of'the invention illustrated in Figs. 1 to 3, the connectionbetween the levers 5 and 6 comprises a two-part top rod, one

part 7 ofwhich is in the form ofa rackbar having teeth 8 formed thereon, said part 7 of' the top rod being pivotally connected to the live truck lever 6, at9. The other part 10 of the top rod is pivotally connected to the cylinder lever 5, by a pin 11. Y

A main housing is provided, having an aperture therethrough in which the rack bar 7 slides, its movement being limited by means of a dog 22 mounted in a well 20 formed in the said main housing, said dog 22 engaging ;--the teeth 8 of the rack bar 7, and being held normally in engagement therewith by means of a coil spring 24. The main housing is provided with an upwardly extending por- I tion 15, which is provided with internal 0 ?threads, to which is fitted a threaded portion formeda well 19, in which is mounted a dog 21, whichis held normally in engagement with the ratchet teeth 8 on the rack bar 7, a coil spring '23 serving for this purpose.

Thewell 19 has an upwardly extending:

portion, provided with two apertures,

through the lower of which the rack bar 7 slides. The upper: aperture 12 permits the auxiliary housingto slide uponthe top bar 7 10 which forms a guide therefoigand also prevents the top rod 10,'from sagging when the brakes are in released position.

A fixed stop bracket 25 issecured to the car (not shown)in'position to be engaged by the wall of the well 19, in such manner as thrust'the telescoping sleeve 13 of the auxiliary housing to the leitand cause its to engage in thenexttooth 8 of the rack bar 7.

When it is desiredto apply new shoes, the

top rod is disconnected at the cylinderlever 5 and the rod-10 :is turned'a quarter turn.

This turns the housing assembly on the rack' bar 7, and the rod and housing are pulled forward until-itrstrikes the cotter pin' stop 18: The rib 8O-on the rack makes it neces-- saryfor the car. repairer to turnthe rodlO back-like he'fou-nd it, thereby resettingthe dogs 21' and 22 to 'mesh teeth8on the rack bar-'7.

Upon-restoring'the partsto their former position,-.the :dogsfZI-and 22 will be initially engaged with the teeth8 oftherack bar 7' properly with the with which they, happen' to align, but it'is. apparent that when the top;rod 10is drawn to. the right, and the face ofwell 19 strikes the stop bracket 25, the dog; 21 will be brought to rest, and any further movement of rod 10 towards the right'will result in causing the" next succeedingxtooth orrteeth -8 of therack bar 7 to pass over and be engaged'bythe dog;'21, the spring. 17 being. compressed in this action; When: the force tending'to move dog 21' rod 10 to the right is released, the spring 17 will act to thrust the dog 22 to the left, to engage succeeding teeth 8 of the rack bar 7, and thus an automatic take-up of undesirable slack is efiiected, and the proper effective length of the top rod 10 is maintained under all conditions of use, irrespective of variations in the thickness oi: the brake shoes.

To permit the quarter turn of the housings and associated parts referred to, the rack bar 7, which is circular in cross-section, is provided with a rib 30, which travels in a groove 31, formed in the connecting portion 15*" which lies between the part 15 and the sleeve 13.

As shown in Fig. l (to which the same reference numerals have been applied in so far as they are applicable), I provide for a construction in which either end of the top rod may be disconnected for the purpose of replacing the worn-out shoes. In this construction, the rack bar 7" is provided with a longitudinal opening which extends therethrough, and through this opening extends a part 7 of the top rod. This part 7 is secured to the live truck lever 6 in the same manner as has hereinbefore been described for securing the rack bar 7 thereto. The other end of the rod 7 is provided with threads 7, which are fitted to internal threads out adjacent the outer end of the longitudinal opening in the part 7*. A suitable lock nut 7 serves to hold the part or rod 7 in proper position. In constructing the rack bar 7", I cast or form thereon a flange T, which contacts the auxiliary housing and prevents accidental withdrawal of the rack bar 7 The operation of the device is the same in each case.

It is to be understood that the invention is not limited to the precise construction set forth, but that it includes within its purview whatever changes come fairly within either the terms or the spirit of the appended claims.

Having described my invention, what I regard as new, and desire to secure by Letters Patent of the United States, is:

1. In a brake rigging, a two-piece top rod which constitutes a connection between a cylinder lever and a live truck lever, a part of said rod bein provided with a row of ratchet teeth, the other part of said rod carrying a housing which encloses said ratchet teeth, a sleeve in said housing, an auxiliary housing slidably secured to said other part of said rod, a telescoping sleeve thereon slidable on the first mentioned sleeve, dogs in said housings which normally engage said ratchet teeth, and a stop against which said auxiliary housing abuts when the brakes are set.

2. In a brake rigging having cylinder levers, brake shoes, live truck levers, lower rods, two-piece top rods, and means to actuate the same, ratchet teeth formed on one part of the top rod, one end of which is pivotally secured to the live truck lever, a housing fixedly se-' cured to the other part of the top rod, said ratchet teeth passing through said housing, a sleeve in said housing, an auxiliary housing slidably mounted on said other part of the top rod, a telescoping sleeve on said auxiliary housing which telescopes the first named sleeve, a spring which holds them normally separated, a dog in each housing which engages said teeth, and a permanent stop against which said auxiliary housing abuts when the brakes are set.

3. In a device of the character described, the combination with a brake rigging having cylinder levers, brake shoes, live levers, lower rods and two-piece top rods which connect said cylinder levers and said live truck levers, one of said pieces having ratchet teeth thereon, the other being smooth, automatically operated means secured to said top rods which will shorten the same as the brake shoes wear, said means comprising a fixed housing, an auxiliary housing, a pair of telescoping sleeves on said housing, a spring which normally holds them separated, means on said housing which engage and hold said rods, an upwardly extending portion on the auxiliary housin which "forms a guide for the smooth piece or' the top rod, one end of each two-piece top rod being pivotally secured to the cylinder lever and live truck lever respectively.

4. A structure as recited in claim 1, in combination with a spring in said sleeves, and tending to thrust them apart.

5. A structure as recited in claim 1, in combination with a well associated with each of said sleeves, a dog in said well, a spring in the well tending to thrust the dog into ongagement with said ratchet teeth, and means tending to thrust the sleeves apart.

6. A structure as described in claim 3, in combination with a tubular rack fixedly mounted on one part of each top rod, the other part of said rod carrying a housing which encloses said tubular rack, a sleeve in said housing, an auxiliary housing slidably secured to said other part of said rod, a telescoping sleeve thereon slidable in the first mentioned sleeve, means tending to thrust the sleeves apart, spring-actuated dogs in said housings, and a stop for said auxiliary housing.

HARLEY E. ANDERSON. 

